Why The Individual Ranks For Each Role?

The whole idea of individual ranks for each role just sounds awful. What if I’m decent at two roles? I main adc, but I have a few champions with m7 in mid. This whole idea just makes it so that I have to play one role and that’s it. Look, adc gets boring sometimes, especially when I’ve been playing the same meta champs over and over, when an example being Varus and Jinx. Let’s say that I am able to play Evelynn pretty well (mastery 7 btw) and want to play her to feel something new. If i’m already plat in the adc role, doesn’t that mean I have to do promos entirely again? And have to start at a whole new rank again? That would just feel awful. I’d rather take a break from league than have to start at a whole 1-2 divisions down. Like if I play as adc for 20 games, let’s say I reach gold 1. Then I switch to jungle and play another 20 games to only reach gold 1 on that position as well. THERES NO PROGRESSION. Another problem would be smurfing. Let’s say I have a friend in silver 3. I can just duo with him as an carry role even if I’m way higher than him on the ladder. It’s legit smurfing without making a new account. Finally, the queue times. With support being (maybe) one of the most least played roles, there’s just not gonna be enough players to be able to wait for a person to queue up as a support. And there’s no way they can do an auto fill with this system. This whole idea just seems unnecessary. It hinders progression, it hinders variety, it hinders a fair match up, and finally, it hinders the fun in ranked.